A design flaw was the root cause of the Sept. 5, 2014, plane crash that caused the death of Rochester real estate developer Larry Glazer and his wife Jane.

That's the conclusion spelled out in a final accident report released by the National Transportation Safety Board this week.

An investigation of the wreckage found that an overheat switch had been activated, cutting off the air supply to the cabin of the plane.

The report concluded that the design of the cabin pressurization system, was "prone to unnecessary shutdown," and that the pilot's emergency checklist "prioritized troubleshooting over ensuring that the pilot was sufficiently protected from hypoxia."

Glazer asked air traffic controllers if he could move to a lower altitude, which the NTSB concludes was his immediate reaction to sensors indicating the pressure problem. However, they found that his apparent failure to immediately don an oxygen mask impacted his decision-making ability.

Jane Glazer of Brighton, owner of QCI Direct of Chili, smiles at the presenters while heading back to her seat after giving a brief speech after winning one of the Rochester Business Ethics Award at the Riverside Convention Center in Rochester on September 18, 2012. TINA YEE staff photographer

A model airplane with Larry and Jane Glazer's names sits in an office window at Buckingham Properties. Both Larry and Jane were killed Friday when their plane crashed outside of Jamaica. LAUREN PETRACCA/@LaurenPetracca/ STAFF PHOTOGRAPHER

Partners in Buckingham Properties, a local real estate company that buys and renovates older city buildings. Larry Glazer (l) and Harold Samloff were the driving forces behind the renovation of Monroe Ave. near downtown twenty years ago and now have moved to rehabing manufacturing buildings. Shown here outside their office at Monroe Ave. and Oxford St. Karen Mitchell Staff file photo

"The pilot showed evidence of deteriorating cognitive abilities about 2 minutes 30 seconds after he initially reported the problem to ATC [air traffic controllers]," the report said. "Ultimately, the pilot had less than 4 minutes to detect the pressurization system failure CAS [crew alerting system] messages, report the problem to ATC, locate the proper procedures in a voluminous POH [pilot's operating handbook], and complete each procedure, all while suffering from an insidious and mentally impairing condition that decreased his cognitive performance over time."

The loss of cabin pressure, the NTSB concluded, rendered both the pilot and passenger unconscious. The plane continued to fly until it ran out of fuel and crashed into the ocean, killing both occupants.

The Glazers, prominent local real estate developers and philanthropists, had taken off from the Greater Rochester International Airport at 8:26 a.m. the day of their fatal flight, and were bound for Naples, Florida, where they had a vacation home.

Larry Glazer, an experienced pilot, was at the controls at 28,000 feet around 10 a.m. when he radioed air traffic controllers to report "an indication that is not correct in the plane" and asked permission to descend to 18,000 feet.

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Larry Glazer's comunication with Atlanta Air Control indicating there is an issue with his plane.
File video

Controllers initially cleared Larry Glazer to go down to 25,000 feet, which he did, but when they directed him to descend to 20,000 feet a few moments later, his speech had become slurred and he didn't respond.

Two Air National Guard fighter jets who were dispatched from South Carolina to intercept the plane reported seeing Larry Glazer slumped over the controls but breathing and the cockpit windows frosting over.

The jets shadowed the Glazers past Florida and over the Bahamas, but disengaged prior to the plane entering Cuban airspace, where it gradually descended as the engine ran out of fuel and crashed into the Caribbean Sea.

The Glazers were both 68 years old.

The Glazers’ son Richard said Thursday the family was “very happy” with the NTSB report.

“It took three years, but these guys did amazing detailed work,” he said. “A lot of it is due to the fact that we salvaged the aircraft. They were able to get good information.”

The plane crashed off the coast of Jamaica in water that was thousands of feet deep. The government was unable to recover the aircraft, but the family financed a salvage effort that brought both the Socata and their parents’ remains to the surface about four months after the accident.

Glazer said the NTSB found a design flaw with the pressurization control system. The agency also concluded that the training manual for the Socata TBM 900 was lacking in that it provided little information about dealing with a depressurization event and the sections that did discuss such events encouraged pilots to problem-solve before putting on their oxygen masks.

Daher-Socata has since reversed the order, now instructing pilots to don their oxygen masks before doing anything else in much the same way airline passengers are told to put on their own masks before helping their children.

“Socata has changed their manuals, which is a blessing, because everyone flying these aircraft are now safer,” Glazer said.

He acknowledged that the NTSB report found some shortcomings on the part of Laurence Glazer. The switch that allowed oxygen to flow to oxygen masks in the cockpit was found in the “off” position, for instance, and the pilot failed to descend properly after the depressurization episode began.

But neither of those factors was listed as contributing to the accident. “There’s very little talk of pilot error, which is positive for the family,” he said.

A wrongful death lawsuit filed by the elder Glazers’ estate against Daher-Socata and a number of companies that supplied components or services to the manufacturer is on-going in state Supreme Court in Rochester.

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Ken Glazer filed a wrongful death lawsuit on behalf of his parents, Larry and Jane Glazer, who died in a plane crash in 2014. (Sept. 20, 2016)
Olivia Lopez